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Coloma, J.

Publications and source records attributed to Coloma, J..

2 recordsLinked to original sources

Genetic variation of Aedes aegypti populations from Ecuador

This is the first genetic analysis in Ecuador of Aedes aegypti using fragments of mitochondrial genes, NADH dehydrogenase subunit 4 (ND4) and cytochrome oxidase subunit I (COI). A total of 154 mosquitoes from 23 localities were collected in the Pacific coastal lowlands, Amazon basin lowlands, and the Galapagos Islands from 2012 to 2019. The analysis of fragments of the genes COI (672 bp) and ND4 (262 bp) and concatenated analysis of both COI and ND4 showed two haplotypes (H1, H2) present in Ecuador mainland and the Galapagos Islands. The phylogenetic analysis identified two well-supported clades. Combined analysis of both genes from ten localities also resulted in two haplotypes. Nucleotide diversity, neutrality tests (Tajimas test D, Fu and Lis F*and D*) and AMOVA analysis of the entire data set suggest balancing selection for both genes. The results indicate genetic variation without geographical restriction. COI-H1 grouped with sequences from the Americas, West and Central Africa, East Africa, Asia, and Australia. ND4-H1 grouped with similar sequences from the Americas, Asia and West Africa. COI-H2 grouped with sequences from Asia and the Americas. ND4-H2 grouped with sequences from the Americas. We report overlapping peaks in four sequences that suggest heteroplasmy in the individuals. The origin of the populations of Aedes aegypti in Ecuador show African genetic origin and are widely present in several countries in the Americas. One of the genetic variants is more common in all the localities and the two haplotypes are distributed indistinctly in the three geographical sampled areas in Ecuador.

genetics

Oropouche virus cases identified in Ecuador using an optimised rRT-PCR informed by metagenomic sequencing

Oropouche virus (OROV) is responsible for outbreaks of Oropouche fever in parts of South America. We recently identified and isolated OROV from a febrile Ecuadorian patient, however, a previously published rRT-PCR assay did not detect OROV in the patient sample. A primer mismatch to the Ecuadorian OROV lineage was identified from metagenomic sequencing data. We report the optimisation of an rRT-PCR assay for the Ecuadorian OROV lineage, which subsequently identified a further five cases in a cohort of 196 febrile patients. We isolated OROV via cell culture and developed an algorithmically-designed primer set for whole-genome amplification of the virus. Metagenomic sequencing of the patient samples provided OROV genome coverage ranging from 68 - 99%. The additional cases formed a single phylogenetic cluster together with the initial case. OROV should be considered as a differential diagnosis for Ecuadorian patients with febrile illness to avoid mis-diagnosis with other circulating pathogens.

genomics